Evaluate suppression of gonadotrophins in response to Nestorone and Testosterone gel compared to Testosterone gel. CENTRAL LABORATORY FOR THE STUDY ON THE 28 DAYS REPEAT-DOSE SAFETY AND TOLERABILITY, PHARMACOKINETICS, AND PHARMACODYNAMICS STUDY OF COMBINED NESTORONE/TESTOSTERONE GEL IN HEALTHY MEN The objective of this Task Order is to obtain valid and reliable data for the effect of Testosterone Gel and of a combination ofNestorone and Testosterone Gel on serum hormone levels.